Ford V10 knock problem

[JohnB]

We just came back from our yearly Sunline road trip, 1,608 miles and 18 days. It was great! But the truck starting acting up.

About ½ way into the trip I start getting this really bad gas knock sound but only when the truck needs more fuel to keep up the same speed. Towing 60mph down the highway pulling 9,200# and level ground it is quiet until I feed it some more gas and then knock, knock, knock. This is a gas knock sounds on steroids. I even tried a 1/2 a tank of 89 octane and it did not change a thing other then get slightly worse mpg.

Well after I made it to camp and it cooled off I crawled under to make sure I was not grinding something up. Nope all the exhaust is tight and nothing touching anything on the drive line. It even does the knock with no camper and idling in the parking lot moving 5 mph. Again only when I feed it more gas. If the truck is rolling and not feeding the gas all is quiet. But it takes about 5 minutes to warm up before it starts. H’mmm

No loss of power that I can detect just the knock. So after I made it to the next campground I crawled under and saw a fine soot spot on the exhaust manifold. H’mmm OK Let’s look deeper.

Here is the soot spot. Look at the edge of the manifold and the head.


I did not have a feeler gage in my camping trip repair kit (will next time) but I went back to the basics. Paper… So I use a corner off a strip of paper that is about 0.005 to 0.007” and probed away. Yup it went right in. Oh great. At least a 1/4”. I stopped and didn’t try any deeper as it was hard enough reaching up to get that part in. I found what I was after.


I have not had the manifold off but the wall thickness of that casting can’t be a lot more then 1/4 to 3/8. Due to work being crazy since we made it back I have not had time to look any further. I have a feeling I have the V10 cracked manifold stud disease or a blown gasket. I have all 20 studs and nuts showing out of the manifold but the stud could be cracked and rusted in the manifold and not fall out. I need to do some more research on this before I tear into it. And all new studs, nuts, gaskets and a helicoil kit as a start.

Before the trip I put new rotors and new brakes on the rear and a new serpentine belt. That was a day job 3 days before we headed out. I thought that was going to be it but not yet… Have to keep these camper TV’s a running.

More as this develops.

John


PS While I have to take the fender wells pout to get to all this, I guess it's spark plug time too. 72,00 miles I'm in the league and heard they crack off in the head some time when your over 100K miles. Oh well….

[EMD_Driver]

Hey John...

When I first started reading your post, I was reminded about what my 97's exhaust was doing. When I put it under load, I heard a distinctive "Knock" It turned out, that the rear manifold bolt on the driver's side was gone! If that wasn't bad enough, the next three were all loose!

I pulled everything and installed a manifold gasket and new studs. The 7.3's didn't originally come with gaskets and I figured there could have been some warping. Once I buttoned it all up, everything was fine!

[JohnB]

Gary

I just spent the last hour and a half reading on the FTE site on V10 broken studs.... There is still about 30 pages to go... I think I need to buy about 2 gallons of PB Blaster to start with.... Most reading so far is on the pre 2005 V10's but one guy has the 2005 V10 like me. Have to read some more.

I have the Ford shop manual for this truck and I'll start reading that too. I'm still trying to figure out what the best replacment is. Go in with manifold bolts or what ever Ford came up with for the next generation stud? I have not yet found what the best thing is. Still reading and most is still a lot about cussing going on about broken studs... There for sure is a design issue with this setup.

John

[Jim-Bev-2363]

JohnB, Wouldn't this be a good time to add a set of tuned headers? I mean, as long as your in there why not get benefit other than just a repair. I've found that tuned headers are a goog thing.

jim

[Hematite]

I'm not familiar with the manifold problem but if your engine has 3 valve heads, you will have a difficult job changing plugs. The key to doing the plug change successfully is to find the factory TSB online, following it exactly, using the one piece plug wrench/ extension made for the engine and keeping a Lisle plug shield extraction tool handy. Run at least one tank of gas through with Techron additive before the spark plug change. Once the plugs are replaced with new plugs with nickel anti seize on the shield, subsequent removal will be easier.

[EMD_Driver]

Originally Posted by JohnB

Gary

I just spent the last hour and a half reading on the FTE site

You will get some great advice from the guys at FTE!

I don't know if you posted a thread there, but they are a lot like us about asking questions!

[JohnB]

Originally Posted by Hematite

I'm not familiar with the manifold problem but if your engine has 3 valve heads, you will have a difficult job changing plugs. The key to doing the plug change successfully is to find the factory TSB online, following it exactly, using the one piece plug wrench/ extension made for the engine and keeping a Lisle plug shield extraction tool handy. Run at least one tank of gas through with Techron additive before the spark plug change. Once the plugs are replaced with new plugs with nickel anti seize on the shield, subsequent removal will be easier.

Rick

Thanks for the info. Yes, I have the 2005 redesign 3 valve V10. Need to do more research on ths plug deal as well before going into it.

Thanks

John

[JohnB]

Originally Posted by Jim-Bev-2363

JohnB, Wouldn't this be a good time to add a set of tuned headers? I mean, as long as your in there why not get benefit other than just a repair. I've found that tuned headers are a goog thing.

jim

Jim

I have thought about a complete Banks system for this truck but it is a 2005 and getting on in age. Still lots of life yet but I have no idea where this gas price deal is heading 3 years from now or even next week for that matter….. If I could ever recoup in gas savings the cost of the upgrade, I might consider the upgrades. I have had a buddy do his pre 3 valve V10 when the truck was fairly new and they did see a performance upgrade but not a lot of mpg upgrade. The HP and torque came close to what I have now as stock with the 2005 engine upgrades. Now granted I’m sure free flowing exhaust will give me a boost in performance but it comes back to the dollars verses the gain.

This engine does not like ethanol in any amount. If I could easily get pure gas it would boost my mpg more I believe then the Banks system could. I have no power problems at all. I know this as 2 years ago I got about 3 full tanks of pure gas in NY and OMG… I could see the mpg gain in front of my eyes. I have never had 13 mpg towing a camper with this truck until then. And as soon as I hit the Ohio state line on the way back that 1 tank did it and back down it goes again like a rock. I was shocked…

Thanks for the thoughts though I may revisit this as if I’m going to do it, now is the time. But I’m back to the unknown of gas prices in 3 years will it be so high my entire long distance towing will be totally different.

Thanks

John

[JohnB]

Originally Posted by EMD_Driver

You will get some great advice from the guys at FTE!

I don't know if you posted a thread there, but they are a lot like us about asking questions!

Yup I know. Most time I just need a hint of where to go looking and the hints come quick from that site.

[Jim-Bev-2363]

JohnB, I have installed headers and the one thing I did notice is the extended life of the motor. Less strain I guess. I gave a old Suburban to my son that had 2 hundred plus on it. Doors were rusting off it was in such bad condition but the motor was strong. He fixed the doors and kept driving that thing for a long time more.

I feel the costs of fuel will rise and that is for sure but there will be a need for the strong muscled vehicles. We do need to inform our elected officials of our problems of low power, destroyed equipment and the taking away of our freedom of recreation in our vehicles of choice. A freedom that has made America great. Bio-fuels are not better, they are only different. It takes more fossil fuels to make the biofuels so nothing has changed but who gets the profits.

Enough preaching to the choir, but if your vehicle lasts longer then your ahead of the game whatever the fuel situation becomes.

jim

[JohnB]

Well had to time today to check the truck further.

The soot spot after a 1,000 miles of towing is now a little more pronounced. This is left side rear cylinder.


And I buried a 3” long 0.005 feeler across the entire back surface of the manifold to the head. You can see it hanging out.


And on the opposite side of the last left cylinder a 0.002 goes right in. You can see the soot sport on the opposite side


Then I went to a 0.002 and started probing other areas. On the same left side the cylinder next to the last I can get the 002 in by the bolt but not the center area.


Then over to the right side next to the starter. Here the same thing with the 0.002. Can get it to start to work in by the bolt but not all the way in. I’m about 3/16” in.


I know the 0.005 all the way across on the left rear cylinder is not right. That is most likely the noise maker. As I start the truck up I now have tick, tick, tick lick the sound of a valve lifter from years ago. That was not like that during the trip when I first noticed this. So it is progressively getting worse.

The 0.002 that can start in on both the left and right sides but not pass all the way in, h’mm do not know what is acceptable. Ideally that joint is dead flat and tight. Have to do some more reading on that one.

The Ford shop manual only told me what torque to put the stud nuts too. Not a lot else. It was also written the start of the year this truck series came out. So new engine and I’m sure they did not know all the issues that can yet come.

More as this progresses.

John

[JohnB]

Originally Posted by Jim-Bev-2363

Enough preaching to the choir, but if your vehicle lasts longer then your ahead of the game whatever the fuel situation becomes.

jim

Jim

This truck can go to 200K miles with out a problem. That is 128K from now. In my current camping situation (until I retire) that will take me well into retirement years and then some. When I head out west for months on end the miles will go up.

I only use the truck now for camping and when son borrows it to haul something. So as long as something else does not change, I see no need to trade this truck. If gas goes out of site in price, well I still have this camper. The trips will get shorter in distance but I have no plans to stop camping any time soon. And as far as burning gas, my prior K2500 Suburban burned almost as much gas towing the T2499 around. It is only 1 mpg difference worse for a truck that can pull 30% more. And I'm not yet ready to go back to the pop up and DW I'm know is not....

I'm hoping for the American way where someone will invent a fuel, additive or conversion kit to make a ton of money on it to add to the older vehicles when the normal fuel channels are out of site in gas.... Or I can go the route Gary did and burn home brew....

[Sunline Fan]

Hi John,

Sorry to hear of your problems. I've had a similar issue with mine, even though it might not be the same problem you have. With mine, the front access plate for the torque converter rattled even though it was tight. I took it off, put silicone on it, and it eliminated probably 60% of the rattle. It too sounded like a gas knock at first and only happened when I'd have my foot in it, and usually around 1700 rpm. If it downshifted, it would go away (or I couldn't hear it at that point).

I've still got a knock type noise, but I haven't investigated further to know what might be causing it. My first thought is injectors, but I'm not sure.

Last January, I decided to try the SCT tuner with custom tuning from 5 Star Tuning. After running about six months with the economy tune with disappointing results, I've switched to performance. I found really no difference mileage wise with the econo, and it might have been slightly worse, and it was really doggy. With the performance tune, I have my V10 back and it is a little quicker. I haven't been running any trips to school to get an accurate highway baseline with the performance, but from what I can tell now with the instant readout, it's easier to do better if you pay attention to throttle input. Will it pay for itself? I'm not sure. It sure doesn't give the paybacks of the diesel products with the mileage gains. But driveability with either tune is much more enjoyable than stock. It holds gears much longer, especially on hills. I haven't put the tow tune on it yet (haven't towed anything), so I can't comment on how that is. I'm sure it would really help hold OD at 65ish with the 3.73 rear.

At $400 (and FTE discount), it's a lot cheaper than a Banks kit for comparable power gains.

I agree, I've heard the 3V plugs are much more difficult to change, and there is a special tool that helps to pull them. Dona and Charlie (Clueless Campers) were telling me at the M&G that they changed the plugs on their 3V truck and found out that they needed the special tool too, and they had to go all over town to find one. Definitely find one before you start the job...

Also, if you do plugs, make sure to do the coil boots too. I've yet to find out if there's a way to test the coil packs, but one of those could be bad too. I've been told that auto parts stores do sell the boots separately. I guess what happens is the rubber gets formed around the old plug and when the new one goes in, it doesn't seal the same. That gap causes a bit of a miss that will make it seem like the new plugs actually made it worse. I did my plugs at 86k and waited until about 110k before I did the boots. My noises are still there, but I've read that for a noiseless engine starting off, you would notice a difference if there's a gap.

[Hematite]

As to the coil boot, if the replacement plug is the same manufacturer, the coil end of the plug should be identical. The boot, although having taken a set, should seal properly as long as the Motorcraft pure silicone grease is used, as described by the shop manual, on the coil boot seal. This grease is quite expensive but necessary to be used even with new boots. Of course, replacing the boots is not a bad idea either.